复数：posteriors
1.(地位上)后面的;(时间上)在后的,(次序上)其次的 (to);【动】尾部的;【解】背部的;【植】接近茎轴处的
1.后部
2.pl.〕 臀部,屁股
1.relating to the back part of something, especially the back part of your body
1.the part of your body that you sit on. A more usual word is buttocks or butt.
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